OBJECTIVE The aim was to determine the benefits of lymphadenectomy and paclitaxel plus carboplatin chemotherapy for stage I ovarian clear cell carcinoma (defined as intra-abdominal disease confined to the ovaries). METHODS Twenty patients with stage I pure clear cell carcinoma of the ovary diagnosed between 1991 and 2001 were divided into two groups: Group A (12 patients, 1997-2001) underwent complete surgical staging including bilateral salpingo-oophorectomy, hysterectomy, omentectomy, and pelvic and para-aortic lymphadenectomy, followed by paclitaxel and carboplatin chemotherapy. Group B (8 patients, 1991-1996) underwent bilateral salpingo-oophorectomy, hysterectomy, and omentectomy without lymphadenectomy, followed by cisplatin-based chemotherapy. The survival of the two groups was compared. The clinical characteristics of the two groups were evaluated for age distribution, grade, substage, preoperative CA-125, presence or absence of endometriosis, and maximal tumor diameter. RESULTS The estimated 4-year survival rate was 76.9%. The clinical characteristics of the two groups were similar, except for lymphadenectomy and regimen of chemotherapy. With a median follow-up of 36 months (range: 11-130 months), one of 12 patients in Group A had recurrence in comparison with 6 of 8 patients in Group B (P = 0.004). The estimated 3-year recurrence-free survival and 4-year overall survival for Group A was significantly greater than that for Group B (91.7 vs 33.3%, P = 0.014; 100 vs 50%, P = 0.014). Median time to recurrence was 8 months. CONCLUSIONS Complete surgical staging, including pelvic and para-aortic lymphadenectomy and paclitaxel plus carboplatin chemotherapy, appeared to be capable of improving survival of patients with stage I ovarian clear cell carcinoma.